India Starts Closer Study On Migration Of Its Yellowfinff

Source: The Hindu

In a bid to ensure sustainable management of tuna fish in the Indian Ocean, a project to tag the commercially-exploited fish with Satellite-tracked Pop-up Standard Archival Tags (PSAT) had been launched to study its habitat, environmental preference and migratory route.

The project, ‘Satellite Telemetry Studies of Tuna in the Indian Seas’ ( SATTUNA) was initiated by the Indian National Centre for Ocean Information Services (INCOIS) in collaboration with Central Marine Fishery Research Institute (CMFRI), Fishery Survey of India (FSI) and Centre for Marine Living Resources and Ecology (CMLRE).

While 20 Yellowfin Tunas were tagged on an experimental basis off Visakhapatnam, Chennai and Lakshadweep Islands between December 2011 and April 2012, another 25 will be tagged from October this year. The tagging would be continued in the coming years to develop comprehensive data on the environmental and biological parameters influencing the tuna habitat and its migration in the Indian Ocean.

Observing that it was an ocean-wide migratory species, T. Srinivas Kumar, Head of Advisory Services and Satellite Oceanography Group (ASG), INCOIS, said the tagging of the 20 fish had already started providing vital data on temperature and depth information along the migratory routes. “First we need to understand its behaviour and environmental preference to find out if it was available in abundance and manage its sustainability”.

He said that tuna fish was highly exploited in other oceans, including Pacific. Many of the advanced countries had imposed quotas on exploitation of various fish species.

While the Indian Ocean Tuna Commission (IOTC) conducted five tagging cruises between 1988 and 1992 and tagged 995 fish with conventional tags, this was the first time that tuna was being tagged with PSAT.

With only 15 conventional tags recovered then, which was essential to obtain recorded data, alternative method with satellite-tracked tags was taken up as all the vital information could be obtained without recovering the tags.